Search

A reduction in greenhouse gases has become an inescapable requirement. An effective scenario for achieving carbon neutrality is to develop a hydrogen economy. Its success, however, requires strict control of the different processes involved in planned hydrogen chains. The energy chain considered in this paper is a stationary application which involves the production of hydrogen by electrolysis (a power-to gas process) and its combustion in gas turbine combined cycles to generate electricity (a gas-to-power process). In such applications, the need is twofold: (i) to control the risk of explosive atmospheres by performing safe gas detection in the presence of hydrogen and (ii) to secure the reliability of all chain processes using hydrogen-rich gases by achieving reliable analyses of these gases. This paper is dedicated to the development of hydrogen energy to decarbonize the thermal production of electricity. We will first describe the hydrogen chain that would best suit the power generation sector. Then, we will highlight the properties of hydrogen that are critical for its reliable operation. Finally, we will review the sensing technologies suitable for hydrogen-containing fuels. This review paper was published as part of a Joint Industrial Project (JIP) aimed at enabling the safe and reliable deployment of hydrogen energy. [ABSTRACT FROM AUTHOR]

The growing demand for natural gas as a vital energy source underscores the need to optimize gas transportation networks. This optimization involves reconciling conflicting goals, such as maximizing delivery flow rate, minimizing power and fuel consumption, and optimizing line pack. To address this complexity, and introducing a novel multi-objective optimization method that builds upon the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS). The study outlines the fundamental research design, which entails applying the TOPSIS-based multi-objective optimization approach to gas transportation networks. This method generates a range of Pareto optimal solutions, equipping decision-makers with multiple viable options. Key outcomes underscore the efficacy of the proposed strategy. The investigation of three case studies reveals that the TOPSIS-based multiobjective optimization technique yields more economical networks than alternative methods. This showcases its potential in augmenting the efficiency and cost-effectiveness of natural gas transmission networks. In conclusion, this study advances gas transportation network optimization by introducing an innovative multi-objective optimization technique grounded in TOPSIS. The approach offers decision-makers an array of Pareto optimal solutions, aiding their selection of the most favorable one. The results emphasize the technique's capacity to develop economical networks and its versatility across various gas transportation scenarios. Moreover, incorporating this approach into existing optimization frameworks holds the promise of overall enhancements in gas transportation network performance. [ABSTRACT FROM AUTHOR]

The course towards active development of the Arctic zone of the Russian Federation by fuel-and-energy companies involves the development of new methods and approaches to the storage and transportation of natural gas to reduce the negative impact on the ecosystems of cold regions while maintaining the economic feasibility of their use. This work proposes a method for optimizing the technology for transporting and storing natural gas in the form of gas hydrates using soy lecithin as a promoting additive. Experimental methods showed that the addition of soy lecithin to a concentration of 0.5 wt % is on a par with the most efficient promoter of hydrate formation—the surfactant sodium dodecyl sulfate at a concentration of 0.1 wt %. However, a comparison of environmental characteristics demonstrates a clear advantage of soy lecithin. In addition, it was demonstrated that the synthesis of methane hydrate from ground frozen solutions of soy lecithin is at least three times faster than that from liquid solutions. [ABSTRACT FROM AUTHOR]

The need to implement projects for the decarbonization of technological processes is relevant in connection with the international climate agenda. To reduce greenhouse gas emissions, especially in Scope 3, carbon sequestration activities are indispensable, which can be implemented in various ways. Of great interest is the creation and implementation of industrial carbon sequestration technologies that use the existing oil and gas infrastructure, and in addition, allow obtaining additional benefits by increasing oil and gas recovery. The implementation of this technology largely depends on the environmental and economic feasibility of the project, which is influenced by the selected technologies for capturing and cleaning gas from impurities, the length of the pipeline to the field, a reasonable injection technology, an emergency monitoring system, and many other factors. For this reason, scientific and practical research in this direction are of practical importance and are quite relevant. The purpose of our study is aimed at reducing the risks of oil and gas companies in the transportation of carbon dioxide from the place of formation to the place of use when injected into the reservoir to enhance oil or gas recovery. The article presents the results of the analysis of possible emergency situations during the transportation of carbon dioxide to the place of injection. Recommendations are given to prevent them, namely, equipping the route of the pipelines being designed with pressure sensors, justifying the reaction time to stop the compressor equipment, which is no more than 6 minutes and the departure of technical specialists to the emergency facility no earlier than 15 minutes after the incident. It is noted that in order to reduce pipeline corrosion and prevent carbon dioxide leaks, it is recommended to comply with the conditions under which the gas is in a supercritical state, in addition, to purify the gas from impurities in the transported carbon dioxide stream and use a corrosion-resistant material for the manufacture of the pipeline. [ABSTRACT FROM AUTHOR]

This paper presents the results of the study of hydrate formation kinetics at 273.2 K and initial pressure of about 5 MPa in powder hydrogel systems stabilized by hydrophobic nanoparticles. The influence of the aqueous phase used to saturate hydrogel on hydrate formation kinetics was studied. The stability of the systems in hydrate formation–dissociation cycles, i.e., their ability to maintain the hydrate growth rate and water-to-hydrate conversion at a high level in multiple reuses, was assessed. [ABSTRACT FROM AUTHOR]

Here, the concept of "aerofluidics," in which a system uses microchannels to transport and manipulate trace gases at the microscopic scale to build a highly versatile integrated system based on gas‒gas or gas‒liquid microinteractions is proposed. A kind of underwater aerofluidic architecture is designed using superhydrophobic surface microgrooves written by a femtosecond laser. In the aqueous medium, a hollow microchannel is formed between the superhydrophobic microgrooves and the water environment, which allows gas to flow freely underwater for aerofluidic devices. Driven by Laplace pressure, gas can be self‐transported along various complex patterned paths, curved surfaces, and even across different aerofluidic devices, with an ultralong transportation distance of more than 1 m. The width of the superhydrophobic microchannels of the designed aerofluidic devices is only ≈42.1 µm, enabling the aerofluidic system to achieve accurate gas transportation and control. With the advantages of flexible self‐driving gas transportation and ultralong transportation distance, the underwater aerofluidic devices can realize a series of gas control functions, such as gas merging, gas aggregation, gas splitting, gas arrays, gas‒gas microreactions, and gas‒liquid microreactions. It is believed that underwater aerofluidic technology can have significant applications in gas‐involved microanalysis, microdetection, biomedical engineering, sensors, and environmental protection. [ABSTRACT FROM AUTHOR]

Accidents on gas pipelines cause significant damage to the national economy and the economy of the state. Thus, it is necessary to always be prepared for such situations in order to restore the normal operation of the gas pipeline as soon as possible. An important role is played by the execution time of the control actions to localize the accident, pump out the gas, and change the operating modes. It is essential that such control be undertaken, especially if such a situation occurs near a gas-measuring installation for measuring the amount of vented gas. Therefore, the control actions must be error-free in order to quickly stop the non-stationary process, which can lead to undesirable consequences. The paper presents a mathematical model of the operation of the pipeline, developed for the management of the pipeline in an emergency. The analysis of the problem of the occurrence of accidents was carried out, and the effect of liquid on its walls was modeled when the operating mode of the pipeline changed. An example is presented using a numerical model carried out in ANSYS, as well as being analyzed analytically. The results of the calculations are presented, and special attention is paid to the parameters influencing the change in the operating mode of the pipeline. [ABSTRACT FROM AUTHOR]

Recently, research focus has shifted from the prevention of hydrate formation in oil/gas pipelines, to the utilization of gas hydrate in various areas of application, such as cold storage, district cooling, and gas transportation. This study, investigated the pressure drop and flow pattern analysis of CO2 hydrate slurry in the presence of anti-agglomerant in a flow loop. A series of experiments were carried out on CO2 hydrate slurry with (10 to 32) % mass fractions at flow rates of (5 to 7) kg/min in the presence of (0, 0.3, 0.5, 0.7 and 1.0) wt.% concentration of Tween 80 (Polyoxyethylene (20) sorbitan monooleate) in a flow loop. The results show that the CO2 hydrate slurry can be divided into two zones based on the pressure drop and temperature behavior; an active formation region, and a less active formation region. It was found that as the hydrate slurry mean flow rate was increased, the gradient of the pressure drop increased. From the flow visualization, three different flow regimes exist for CO2 hydrate slurries, namely homogeneous, heterogeneous, and bedding flow, and those flow regimes were highly dependent on the hydrate fraction in the slurry mixture. [ABSTRACT FROM AUTHOR]

In gas pipeline networks, the set-points should be carefully tuned to minimize the fuel consumption of compressor stations and meet the network requirements. In practice, the real demand has some variations over the forecasted one and consequently utilizing an appropriate controller to minimize the fuel consumption and manage the network variations is inevitable. The model predictive control is a great choice for systems with long delay such as gas networks. In this paper, an intelligent nonlinear model predictive control of a gas pipeline plant is proposed. It models the plant in fully transient state by a multi-layer perceptron neural network. The prediction power of the neural network is used to predict the plant output over a receding horizon. Initially, the network is trained offline and is then paralyzed with the real plant for online training. The proposed strategy consists of two main stages. In the first stage, the compressor set-points are optimized in the open loop condition considering the forecasted demand over a receding horizon and the resulting output pressures are chosen as the reference trajectories for the closed loop system. In the second stage, the controller is applied to compensate the demand variations. The optimization task is carried out using particle swarm optimization gravitation search algorithm (PSOGSA). Numerical results confirm the accuracy and robustness of the proposed controller in the presence of demand variations, noise and uncertainties. [ABSTRACT FROM AUTHOR]

The article considers the technology absorption natural gas dehydration, systematization of the physical processes occurring in the technological chain of preparation of natural gas. Built fuzzy causal model of the process gas drying based on the combined application of fuzzy inference and neural network approximation. The use of the model enables the structural and parametric optimization of production, aimed at improving the quality of preparation of natural gas. [ABSTRACT FROM AUTHOR]

This study assembles a pipeline mist spraying experiment rig and measures the motion characteristics of water mist in the square pipeline using Particle Image Velocimeter. It explores the settling law of water mist in the pipeline with various spraying pressure and airflow velocity and analyzes their influences. The results indicate that the settling volume increases by 96% in the 1 meter long downstream pipeline, when the spraying pressure increases from 0. 1 MPa to 1. 3 MPa at a set airflow velocity, which is mainly caused by impinging. And the settling volume reduces by 76% in the other parts of the pipeline, which is caused by inertance. But when airflow velocity increases from 1.1 m/s to 10.4 m/s with a set spraying pressure, the settling volume reduces by 24% in the 1 meter long pipeline and reduces by 17% in the other parts. The results will provide a reliable theoretical basis for gas explosion suppression and the parameter setting of water mist in the safe transportation of low concentration gas. [ABSTRACT FROM AUTHOR]

• Different degree of mutual interference among needles is observed in experiments. • The EHD force in the plasma model is used to analyze the mutual interference. • The magnitude of the EHD force is used to quantify the mutual interference. • The EHD force is affected by the space charge and the electric field with different needle arrangements. The ionic wind pump with multi-electrode arrangement is helpful in enlarging its application. However, the arrangement has an inherent mutual interference among the electrodes during discharging process, which have a vital influence on the transportation performance of the ionic wind pump. Meanwhile, the relevance between the mutual interference and the intensity of the ionic wind has not been clearly revealed. In this study, the gas transportation experiments of the multi-needle electrode ionic wind pump are conducted. The intensity variation of the ionic wind with mutual interference is observed in the experiments. A simulation model based on the plasma transportation is proposed to describe the multi-needle discharging process with mutual interference effect. The EHD force is used as the indicator parameter for the intensity of the ionic wind. The experimental results show that the measured mass flow rate of the ionic wind pump is enhanced under dual-row needles and weakened under triple-row needles. Based on the simulation results, the above phenomenon is attributed to variations of the space charge and electric field induced by multi-needle discharging. The added needle electrodes reduce the electric field intensity per needle while increasing the net negative charge in the space. Due to the discharging interference among the needles, the increment of the net negative charge is not proportional to the number of needles. As a result, comparing the three arrangements from the simulations, the electrohydrodynamic (EHD) force of each needle, which is the electric field intensity multiplying by space charge density, increases approximately 45.8% under dual needles and decreases approximately 38.1% under triple needles. The conclusions obtained in this paper can help to guide the design and optimization of the multi-needle ionic wind pump. [ABSTRACT FROM AUTHOR]

Underwater bubbles are unavoidable in the natural world and industrial production. Understanding the behavior of underwater bubbles and manipulating gas bubbles are vital important to both fundamental scientific research and industrial application. Although there has been some progress in controlling underwater bubbles, continuous underwater bubble collection and transportation remain challenging targets. Herein, inspired by the mechanism of water spider's gas storage, a strategy to collect and transport underwater gas bubble is demonstrated by design of a single‐layer underwater superaerophobic mesh (USM) assembled with a quartz tube. Gas bubbles supplied by a syringe pump penetrate the mesh pore and then gather to form a gas column in the quartz tube. Collapse occurs when the gas column reach the maximum storage height/pressure. Under a continuous supply of gas bubbles, the change of pressure becomes a cyclic process, which acts in a pump‐like manner to transport bubbles continuously from the water to the gas phase in the USM device assembled with an asymmetric U‐tube. This novel gas collection and transport system provides a new inspiration for developing new technologies for applications in pipes, sensors, gas collection, and environment protection. [ABSTRACT FROM AUTHOR]